docstr: Bandwidth used by the long-run covariance estimator
docstr_tok: ["Bandwidth","used","by","the","long-run","covariance","estimator"]
code: def bandwidth(self) -> float:
      """Bandwidth used by the long-run covariance estimator"""
      return self._kernel_est.bandwidth
  
imports: from __future__ import annotations
  from typing import cast
  import numpy
  import pandas
  from scipy import stats
  from statsmodels.iolib.summary import Summary
  from statsmodels.iolib.table import SimpleTable
  from statsmodels.regression.linear_model import RegressionResults
  import arch.covariance.kernel
  from arch.typing import ArrayLike1D, ArrayLike2D, Literal, UnitRootTrend
  from arch.unitroot._shared import KERNEL_ERR, KERNEL_ESTIMATORS, ResidualCointegrationTestResult, _cross_section
  from arch.unitroot.critical_values.phillips_ouliaris import CV_PARAMETERS, CV_TAU_MIN, PVAL_LARGE_P, PVAL_SMALL_P, PVAL_TAU_MAX, PVAL_TAU_MIN, PVAL_TAU_STAR
  from arch.unitroot.unitroot import TREND_DESCRIPTION
  from arch.utility.array import ensure2d
  from arch.utility.io import str_format
  from arch.utility.timeseries import add_trend
label_desc: Use image node_id 3 for calling the PhillipsOuliarisTestResults obj's underlying member method code with example usage: obj.bandwidth() and returns: self